/*
 * Copyright (c) 2010, 2020 Oracle and/or its affiliates. All rights reserved.
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.glassfish.grizzly.http.server.util;

import java.util.LinkedHashMap;
import java.util.Map;

/**
 * Extended implementation of <strong>LinkedHashMap</strong> that includes a <code>locked</code> property. This class
 * can be used to safely expose Catalina internal parameter map objects to user classes without having to clone them in
 * order to avoid modifications. When first created, a <code>ParameterMap</code> instance is not locked.
 *
 * @author Craig R. McClanahan
 * @version $Revision: 1.4 $ $Date: 2007/06/18 17:41:35 $
 */

public final class ParameterMap extends LinkedHashMap<String, String[]> {

    // ----------------------------------------------------------- Constructors

    /**
     * Construct a new, empty map with the default initial capacity and load factor.
     */
    public ParameterMap() {

        super();

    }

    /**
     * Construct a new, empty map with the specified initial capacity and default load factor.
     *
     * @param initialCapacity The initial capacity of this map
     */
    public ParameterMap(int initialCapacity) {

        super(initialCapacity);

    }

    /**
     * Construct a new, empty map with the specified initial capacity and load factor.
     *
     * @param initialCapacity The initial capacity of this map
     * @param loadFactor The load factor of this map
     */
    public ParameterMap(int initialCapacity, float loadFactor) {

        super(initialCapacity, loadFactor);

    }

    /**
     * Construct a new map with the same mappings as the given map.
     *
     * @param map Map whose contents are duplicated in the new map
     */
    public ParameterMap(Map<String, String[]> map) {

        super(map);

    }

    // ------------------------------------------------------------- Properties

    /**
     * The current lock state of this parameter map.
     */
    private boolean locked = false;

    /**
     * Return the locked state of this parameter map.
     */
    public boolean isLocked() {

        return this.locked;

    }

    /**
     * Set the locked state of this parameter map.
     *
     * @param locked The new locked state
     */
    public void setLocked(boolean locked) {

        this.locked = locked;

    }

    // --------------------------------------------------------- Public Methods

    /**
     * Remove all mappings from this map.
     *
     * @exception IllegalStateException if this map is currently locked
     */
    @Override
    public void clear() {

        if (locked) {
            throw new IllegalStateException("Illegal attempt to modify ParameterMap while locked.");
        }
        super.clear();

    }

    /**
     * Associate the specified value with the specified key in this map. If the map previously contained a mapping for this
     * key, the old value is replaced.
     *
     * @param key Key with which the specified value is to be associated
     * @param value Value to be associated with the specified key
     *
     * @return The previous value associated with the specified key, or <code>null</code> if there was no mapping for key
     *
     * @exception IllegalStateException if this map is currently locked
     */
    @Override
    public String[] put(String key, String[] value) {

        if (locked) {
            throw new IllegalStateException("Illegal attempt to modify ParameterMap while locked.");
        }
        return super.put(key, value);

    }

    /**
     * Copy all of the mappings from the specified map to this one. These mappings replace any mappings that this map had
     * for any of the keys currently in the specified Map.
     *
     * @param map Mappings to be stored into this map
     *
     * @exception IllegalStateException if this map is currently locked
     */
    @Override
    @SuppressWarnings({ "unchecked" })
    public void putAll(Map map) {

        if (locked) {
            throw new IllegalStateException("Illegal attempt to modify ParameterMap while locked.");
        }
        super.putAll(map);

    }

    /**
     * Remove the mapping for this key from the map if present.
     *
     * @param key Key whose mapping is to be removed from the map
     *
     * @return The previous value associated with the specified key, or <code>null</code> if there was no mapping for that
     * key
     *
     * @exception IllegalStateException if this map is currently locked
     */
    public Object remove(String key) {

        if (locked) {
            throw new IllegalStateException("Illegal attempt to modify ParameterMap while locked.");
        }
        return super.remove(key);

    }

}
